Let's get right to the breaking details on that whistle-blower who leaked top secret documents in the government surveillance of americans. Edward snowden revealed his identity to "the guardian." He know he's a hunted man and looking for a country to give him asylum. Brian ross gives us the latest. Reporter: That's right. He knows the u.S. Would try to catch him and put him in prison but the person responsible for one of the greatest national security leaks in recent american history apparently insisted that his identity be made public after he fled the country for hong kong. My name is ed snowden. I'm 29 years old. Reporter: Snowden said he is a former cia technician who until he disappeared last month was a $200,000 a year civilian contractor for the nsa in hawaii. When you see everything, you see them on a more frequent basis and you recognize that some of these things are actually abuses. I think that the public is owed an explanation of the motivations behind the people who make these disclosures that are outside of the democratic model. When you are subverting the power of government that's way fundamentally dangerous thing to democracy. Reporter: He revealed himself sunday afternoon in this interview posted online by "the guardian" conducted by glenn greenwald in hong kong. This is the truth. This is what's happening. You should decide whether we need to be doing it. Reporter: Snowden said he saw firsthand and became increasingly concerned about the reach of the nsa's electronic surveillance of innocent americans. Even if you're not doing anything wrong you're being watched and recorded. Reporter: And that's why he said he chose to expose secret u.S. Programs that collect the phone records of americans and monitor overseas internet e mays. I sitting at my desk certainly had the authorities to wiretap anyone from you or your accountant to a federal judge to even the president if I had a personal e-mail. Reporter: Snowden said he went to hong kong three weeks ago hiding in a luxury hotel and lining pillows along the door to prevent eavesdropping fearful of what the u.S. Could do to him. You can't come forward against the world's most powerful intelligence agencies and be completely free from risk because they're such powerful adversaries no one can meaningfully oppose them. Reporter: He told abc news he had not seen his son since he moved to hawaii and neighbors said he and his girlfriend moved out around may. He said nothing good happening next and I do not expect to see home again. He said he went to hong kong, robin, because it has a history of allowing free speech but it is also a place ha goss have an extradition treaty with the u.S. All right, brian, thank you. There are so many details coming out, snowden also telling "the guardian" that he told his boss that he needed to be away from work for awhile to receive treatment for epilepsy. Here's more of what he had to say. Specifically targets the communications of everyone. It collects them in its system and filters them and analyzes them and measures them and stores them for periods of time simply because that's the easiest most efficient and most valuable way of getting to the point you don't have to have done anything wrong. You simply have to eventually fall under suspicion from somebody, even by a wrong call and then they can use this system to go back in time and scrutinize every decision you've ever made. I'm just another guy who sits there day to day in the office watches what's happening and goes, this is something that's not our place to decide. Over time that awareness of wrongdoing sort of builds up and you feel compelled to talk about it and the more you talk about it, the more you're ignored, the more you're told it's not a problem until eventually you realize that these things need to be determined by the public. I could be, you know, rendered by the cia. I could have people come after me. If they want to get you they'll get you in time.

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